1. Field of the Invention
This invention relates to an electronic wind instrument and, more particularly, to an electronic wind instrument which generates desired musical tones in response to breath information generated according to breath operations of the player.
2. Description of the Related Art
In the field of keyboard musical instruments, electronic musical instruments with a commonly termed touch-response function are well known in the art. The function which is presently called the touch-response function is one of generating initial touch data or after-touch data according to the key depression speed when a key on the keyboard is operated or a key depression force when the key is further depressed after the key depression operation and controlling the tone volume or tone color of the tone to be generated according to these two data. In the electronic keyboard musical instrument with such a function at the instant of commencement of key depression key-"on" data generated at this time and initial touch data corresponding to the key depression speed are supplied to a tone source, and a predetermined tone is generated with a volume corresponding to the initial touch data when the key-"on" data is provided. When the key having been operated is further depressed after the commencement of tone generation, after-touch data generated according to the key depression force is supplied again to the tone source for the control of the volume or the like of the tone being generated according to the after-touch data.
Heretofore, there has been developed an electronic wind instrument, in which the tone generation is controlled according to a breath operation with respect to the mouthpiece. A typical electronic wind instrument of this type is disclosed in U.S. Pat. specification No. 3,767,833.
In such an electronic wind instrument, however, it is not suited to adopt the technique of the touch-response function used for the electronic keyboard instrument incorporated in electronic musical instruments without any modification. If the technique of the touch-response function used for electronic musical instruments is adopted for an electronic wind instrument without any modification, the following problem will arise.
If the technique of the touch-response function used for electronic musical instruments is used without any modification for an electronic wind instrument, at the commencement of a breath operation with respect to the mouthpiece provided on the wind instrument body key-"on" data generated with the commencement of the breath operation and initial breath data representing the breath operation force, i.e., breathing force, are supplied to the tone source, and a predetermined tone is generated at the instance of provision of the key-"on" data with a volume corresponding to the initial breath data. When the breath operation is continued after the commencement of the tone generation, after-breath data generated with the breath operation force is supplied again to the tone source for the control of the volume, etc. of the tone being generated according to the after-breath data.
However, a breath sensor which is usually used for this type of electronic wind instrument has inferior response to the breath operation force of the player. Therefore, even when the player suddenly gives a strong breath operation force from the outset, the breath output level of the breath sensor can not be suddently raised. Therefore, if the tone volume at the time of the tone generation is determined absolutely on the basis of the sole initial breath data value at the instant when the preset key-"on" value is exceeded as noted above, since the initial breath data at the instant of surpassing of the preset key-"on" value has a comparatively small value, the volume of the tone of at the time of the tone generation is low even when a strong breath operation force is given suddently from the outset. This means that the breath operation state provided by the player can not be adequately reflected in the volume of the tone to be generated.
Further, with an arrangement that a tone is generated immediately with a volume corresponding to pertinent initial breath data when the preset key-"on" value is exceeded by the breath output value from the breath sensor, an unnecessary tone will be generated against the will of the player with a noise breath output produced by a casual breathing or the like other than a breath output produced on the basis of a breath operation by the player.
With the electronic wind instrument disclosed on the U.S. Pat. specification No. 3,767,833, an amplitude modulator is controlled according to an analog breath detection signal detected from a breath sensor, thus generating a tone of a volume corresponding to an analog breath detection signal. Therefore, by gradually increasing the breathing force so that the corresponding analog breath detection signal value is gradually increased, the tone volume level can be proportionally increased. However, with this electronic wind instrument it is possible only to permit the tone volume level to be increased or reduced directly according to and in proportion to the analog breath detection signal. For instance, when the breathing force is gradually increased, the tone volume can not be reduced in proportion to the breathing force, or the tone volume can not be suddenly increased from a predetermined level. Further, it is impossible to alter the contents of the tone color of the tone to be generated according to the breathing force.